Interpretation of field change array data with time domain fractal lightning modeling
Brant E. Carlson1,2, Can Liang2, Phillip M. Bitzer3, Hugh J. Christian3, Nikolai G. Lehtinen2, Umran S. Inan2
1. University of Bergen, Bergen, Norway, 2. Electrical Engineering,
Stanford University, Stanford, CA, USA, 3. University of Alabama,
Huntsville, AL, USA
Despite much study, the physical processes involved in lightning and the
associated electromagnetic emissions remain a mystery, with much effort
thus far devoted to categorizing and describing the emissions. Time
domain fractal lightning (TDFL) modeling provides an opportunity to
improve on such reporting by connecting the observations to theories of
the physics of lightning. Such connection allows meaningful
interpretation of the observations in the context of the physics and
provides better understanding of the behavior of the lightning channel.
We present comparison of time domain fractal lightning modeling with
lightning mapping array data and electric field records from the
Huntsville Alabama Marx Meter Array (HAMMA), a network of field change
meters with high time resolution capable of reconstructing the geometry
and time development of the charge motions in a lightning discharge.
These data are used to constrain the TDFL simulations, while the TDFL
results are used to interpret the field change data. The role of the
evolution of the lightning channel electrical properties, the channel
corona sheath, and the geometric development of the channel are
examined, and the physical implications of the HAMMA data are studied.